This invention relates to slide-plates that allow relative movement between two surfaces with minimal friction, and in particular, slide-plates used at the interface between large rotating machinery components and a stationary foundation.
In large rotary machines such as steam turbines, an associated exhaust hood must be permitted to move axially due to thermal expansion of the steam turbine. Typical exhaust hood thermal expansion is on the order of about ¼ inch, but larger machines may move as much as 1.25 inches. The exhaust hood supports one of the turbine bearings and the low pressure rotor which are sensitive to exhaust hood deflections. As a result, the sliding interface must not negatively impact the bearing stiffness, and must not change elevation over the sliding span.
Current slide-plate techniques includes the use of greased metallic plates as well as flexible vertical plates called “flex legs.” However, such techniques impart large forces on the turbine components due to weight, coefficient of friction, and/or large displacements.